Rocket Lab's new Neutron rocket suffers fuel tank rupture during test

It will be quite a bit longer before Neutron makes it to the launchpad.

Rocket Lab's medium-lift launch vehicle buckled under pressure Wednesday (Jan. 21), when the main stage tank of the company's first Neutron rocket ruptured during an overnight test in Wallops, Virginia.

The "hydrostatic pressure trial," according to a Rocket Lab statement, was meant to push the stage to its structural limit, but was not intended to destroy the vehicle. The company says it is reviewing test data to determine a new timeline for Neutron's debut launch, which had been expected during the first quarter of 2026. "We intentionally test structures to their limits to validate structural integrity and safety margins to ensure the robust requirements for a successful launch can be comfortably met," the Rocket Lab statement reads.

While the Neutron stage seems to be a total loss, Rocket Lab said no serious damage was caused to its facilities or the surrounding test structures.

It's a significant setback for Rocket Lab's newest vehicle, which aims to compete with SpaceX's Falcon 9 payload mass to orbit capacity and partial reusability. Launching Neutron in Q1 2026, which now seems incredibly unlikely, was already a delay from a hoped-for debut by the end of 2025.

As data from the Jan. 21 test is analyzed, Rocket Lab plans to assess its repercussions and continue Neutron's development campaign using the next stage 1 tank already in production, according to the company's statement.

Neutron is a class heavier than Rocket Lab's Electron rocket workhorse, which has seen a steady and consistent increase in small-lift launches over the past few years. Standing more than twice as tall as its Electron predecessor, Neutron clocks-in at 141-foot-tall (43 meters).

The rocket is powered by Rocket Lab's Archimedes engines. Neutron's first stage is designed to be reusable, and able to land on an ocean barge after delivering up to 28,700 pounds (13,000 kilograms) to low Earth orbit.

As for when Neutron will get the chance to deliver such a payload, Rocket Lab says it "intends to provide an update on the Neutron schedule during its 2025 Q4 earnings call in February."